Tungsten Halogen Regenerative Cycle Demystified
Prior to exploring the phenomenon, that halogen cycle is, let me describe the backdrop where it occurs, which is the internal environment of the halogen lamp. Halogen is the generic name for a bunch of elements that include iodine, fluorine and chlorine. A binary compound, which includes a halogen, is known as halide. The central element in the working of halogen lamp is the tungsten filament, which emits photons or light in the visible range, when heated to high temperatures. To protect this filament from getting oxidized or undergoing chemical reactions, the filament is enclosed in a glass bulb, filled with a gaseous mixture, consisting of an inert gas (argon, krypton or xenon - which reduces tungsten's chemical reactivity) and a trace amount of halogen compound (bromine or iodine). Since the tungsten filament in a halogen lamp attains high temperatures, it's generally made up of fused silica glass. The role of the halogen compound will be explained in the following lines. Here is a stepwise explanation of the tungsten halogen regenerative cycle.
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